Magnetic domain memory, popularly known as bubble memory, devices are emerging as a rugged means for data storage particularly suited for hostile environments in terms of shock, vibration and the like. Intel Corporation of Cal., U.S.A., manufactures and sells a bubble memory kit designated BPK 72 in order to facilitate use of, and familiarize circuit designers with, the somewhat exotic bubble memories. A "BPK 72 Bubble Memory Prototype Kit User's Manuel" was published by Intel in 1981 (Order Number: 121685-002), which is not only a guide to the user but is generally a good introduction to bubble memories in general. The publication is incorporated herein by reference in its entirety.
Intel's prototype kit BPK 72 was neither intended, nor is it suitable for actual use except in experimental or laboratory applications. In most applications in which bubble memories would prove particularly advantageous, i.e. in hostile environment applications, it would be desirable to have the bubble memory device proper in a removable module. It is then possible to use a plurality of modules as, say, floppy discs or tape cassettes are used by simply plugging them in and out of a holder in the host equipment.
Unlike a floppy disc or tape cassette, the bubble memory, although a medium for permanent storage without power requirements, must not be disconnected at certain critical times during the operational cycle. Furthermore, and partially due to the complex nature of the control requirements of bubble memories, it is necessary to follow certain sequences in powering down, during insertion and removal, and write protect to maintain the integrity of the circuits driving it and information stored in a bubble memory. Only when these peripheral but necessary requirements are fulfilled would a bubble memory module have a wide scope of application in the environment for which it is most suited, namely the hostile environment.